Self-adjusting clasp for wrist watch bracelets and the like



Aug.. 9, 1938. c. H. KESTENMAN SELF lDJUS'lvING CLASP FOR WRIST WATCH BRACELETS AND THE LIKE Filed June 26, 1935 Patented Aug. 9, 1938 SELF-ADJUSTING CLASP FOR 4PATENT OFFICE WRIST WATCH BRACELETS AND THE LIKE Charles H. Kestenman Providence, R. I., as-

signor to Kestenman Bros. Mfg. Co., Providence, R. I., a `corporation of Rhode Island ,Application June 26,

Claims.

, wearer One object of the present invention is to provide an eXtendible fastening devi-ce for straps, bands or bracelets which is adjustable in length and resiliently operated to maintain the strap or band held snugly about the Wrist of the wearer while adapting it to yield slightly.

Another object of the invention is to provide an eXtensible `fastening device of the type indicated which, after the latter has been placed upon the wrist, may be folded and clasped in closed relationship and thereafter conveniently adjusted to draw the strap or band snugly about the wrist.

Another object of the invention is to provide a device of the type indicated having means whereby the adjusting members may be slid into telescoping relationship to shorten the length of the strap, band or bracelet without disturbing or affecting their clasped or folded condition.

Another object of the inventio-n is to provide an extendible fastening `device of the type indicated 'having resilient connecting means acting `between an extension member and the adjusting means to yieldingly hold the extension member in adjusted position.

Another object of the invention is to provide a device of the type indicated embodied in a simple form of construction adapted for economical manufacture from sheet-metal stock and convenient for assembling without the use of solder, screws or others extraneous parts.

Still another object of the invention is to `provide a device of the type indicated which is neat and ornamental in appearance with its mechanical means entirely concealed from view `and one which efficiently performs its intended `function over long periods of use without repair or replacement `of its parts. i

Further objects of the invention -are set forth in the following specication which` describes a preferred 4form `of construction of the device, by way oiexample, as illustrated by the .accompanying drawing. In the drawing:

Fig. l is a perspective View Showing a conventional type of wrist-Watch having a two-part strapattached thereto with its ends fastened to- 1935, Serial No. 28,526

(Cl. .Z4-71) gether by the present improved extendible clasping device;

Fig. 2 is an enlarged longitudinal sectional view cf the clasping device showing the parts in clasped relationship andthe extension member .-5 in its extreme outward position;

Fig. 3 is a view similar to Fig. 2 showing the holding means for the extension member latched in an adjusted `position with said member eX- tended `from the clasp under the yielding action of the resilient means;

Fig. 4 isa view similar vto Fig. 2 illustrating the manne-r in whichl the parts are unclasped and unfolded to release the extension member and extend the length of the bracelet;

Fig. 5 is a similar view Showing the parts completely opened out;

Fig. 6 is a bottom plan view ofthe device with the parts shown in open relationship;

Fig. 7 is a transverse sectional view of the 20 folded clasp taken `on line 1 1 of Fig. 3 and showing the relation of the detent and ratchet means;

Fig. 8 is a transverse sectional view similar to Fig. F7 taken on line 8 8 of Fig. 2 and showing 25 the manner of clasping the parts in folded relationship;

Fig. 9 is a composite `perspective view of the parts constituting the latching or detent means for adjusting the extension member with re- 30 spect to the foldable members; and

Fig. 10 is a detailed perspective view of a modified form of detent latch` The present improved device comprises in general a series of cooperating members which are 35 hingedly connected at their ends to adapted them to be folded into closed relationship, one over another, or to be opening out into extended posi- `tion to lengthen the strap, band or bracelet having its ends connected thereto. The opposite ends of the strap, band or `bracelet are pivotally attached "to the free ends of the device sothat when the parts thereof are folded into overlying relationship the strap or the like will be drawn snugly around the wrist; and when the folded members are opened out the bracelet will be lengthened to a considerable extent to adapt it to slide over the hand of the wearer.

The present invention. relates particularly to means for adjusting the length of the clasp after the bracelet is placed on the wrist including an extension member and detent means which are `sliclable between a pair of the foldable clasp members. The detent means cooperate with ratchet `means on one of the foldable members.

to permit the extension member to be moved inwardly of the folded members to an adjusted position. The invention further provides resilient means acting between the detent means and extension member to yieldably hold the latter in adjusted position but allowing limited self adjustment of the clasp to adapt the bracelet to expand to prevent binding the wrist of the wearer. The detent means is also adapted to engage an 4abutment at the end of one of the clasp members to limit the outward movement of the extension member when released from the ratchet means.

Referring to Fig. 1 of the drawing, 2 designates a conventional type of wrist-watch having bails 3 on its sides to which the ends of the opposite strap-sections 4 and 5 are attached by means of connectors 5. The present improved extendible clasp or fastening device is herein shown as applied to use with a band or bracelet composed of articulated links, but in other cases it may be employed with a reticulated fabric or leather strap. The term strap is therefore herein employed in a generic sense to designate any such form of band or bracelet. The clasp may comprise three cooperating extension members; namely, a base element 1, a connecting element 8, and a top element or cover 9. These members may be constructed as stampings struck up from sheet-metal stock and curved to conform to the contour of the wearers wrist.

The base member 1 is of trough shape, being constituted by a plate I9 having side flanges II folded upwardly therefrom. As shown most clearly in Fig. 5 the material of the side flanges II intermediate their ends is deformed to provide projecting protuberances or detents I2 for cooperation with the top element or cover 9 to hold the parts in closed folded relationship in the manner and for the purpose as later explained. At one end of the member 1 the side anges II are apertured to receive a hinge-pin I3 around which is looped a connector link I5. The connector I5 may be of any desired construction and, as herein shown, comprises a sheet-metal loop, one end of which receives the hinge-pin I3 with the opposite end embracing a crossbar at the end of the bracelet section 4. The base member 1 is formed at its opposite end with a loop-like bearing I6 through which a hinge-pin I1 extends for pivotal connection with the connecting member 8 in the manner asnext explained.

Theconnecting member 8 consists of a plate I9 with side anges 2l! folded upwardly therefrom. As shown most clearly in Fig. 5, the plate portion I9 has a series of transverse parallel slots 2I which are cut or otherwise formed therein to provide ratchet means for a purpose as later more fully explained. The side flanges 2l] on the member 8 are extended beyondone end of the plate-portion I9 to provide hinge-ears 22 punched with circular holes for receiving the hinge-pin I1 by means of which the members 1 and 8 are pivotally connected at their ends. The opposite end of the plate portion I9 of the connecting member 3 extends beyond the side anges 2E) and is curled to form a loop-like bearing 24 for receiving a hinge-pin 25 on the top or cover member 9, next to be described, whereby the three members 1, 8 and 9 are pivotally connectedto adapt them to be folded together one over another in the manner as later more fully explained.

The top member or cover 9 is constituted by a plate portion 26 having side flanges 21 bent downwardly therefrom. As shown in Figs. 7 and 8 the plate portion 26 is arched to form a central recess 28 extending throughout its length and providing shoulders 29 at the sides of the recess. The outer face of the plate portion 26 may be suitably engraved or otherwise embellished to present an ornamental appearance. The side-flanges Z1 are bent inwardly at the bottom to form narrower flanges 3@ parallel with the plate portion 26 whereby to provide guideways 3! in which the extension member 32, to be later described, is adapted to slide. The plate portion 2S is extended beyond the side flanges 21 at one end to form a projecting lip 33 adapted to serve as a finger-grip for opening the clasp. The opposite extended and reduced end of the plate portion 26 is bent downwardly to provide a stop 34 for the extension member 32 positioned between the side-flanges 21. The articulated members 1, 8 and 9 are adapted to be folded one over the other so that the anges 2Q on the intermediate member 8 lie adjacent and within the flanges II on the base member 1 which, in turn, lie within the flanges 21 on the cover member 9 and in contiguous relation with the edges of the inwardly directed anges 39. The several articulated members are latched in clasped relationship by the engagement of the detents or protuberances I2 on the flanges II of the base member 1 with the edges of the inwardly-directed flanges 39 on the cover member 9 as shown in Fig. 8.

As thus far described the construction and arrangement oi the foldable members 1, 8 and 9 are somewhat similar to previous devices used in the art, it being understood that the end of one strap section 4 is attached to the free end of the member 1 while the end of the other section 5 is connected to the end of the extension member 32 in the cover member 9. By unfolding the connected members of the clasping device the strap or bracelet may be lengthened to adapt it to be slipped over the hand of the wearer without requiring the disconnection of the ends of the strap. The foldable elements of previously used extendible clasping devices are sometimes made adjustable but the constructions have been such that considerable difliculty is experienced in altering the adjustment and further, in all such clasps the adjustment can only be made in definite increments of length. With most previously-used clasps the length of the bracelet is rigidly fixed after an adjustment has been made and as the length of the clasp is altered in definite increments of length the band or bracelet is apt to be either too loose or too tight. Further, such clasps will not yield to expand and contract as the Wrist of the wearer is flexed.

To obviate the deficiencies above noted the present invention contemplates the adjusting of the bracelet to the wrist of the wearer each time it is applied by telescoping or sliding the extension member 32 into the cover member 9. To this end detent means 35 are mounted on the extension member 32 and adapted to slide over the ratchet means on the intermediate foldable member 8 when the extension member is telescoped or slid into the clasp between the cooperating foldable members 8 and 9. The detent means 35 is prevented from movement in the opposite direction or outwardly of the clasping device by its engagement with the edge of one of the apertures 2I forming the ratchet means 75 on the intermediate member 3. Further, the present invention provides a resilient yielding connection between the detent means 35 and the extension member 32 to permit relative movemet therebetween whereb-y the clasp is self adjusting to vary the length of the bracelet to an extent less than the distance between the notches formed by the apertures 2l of the ratchet means; and also to permit expansion and contraction of the band or bracelet to insure at all times a comfortably snug fit upon the wrist of the wearer without any binding tendency.

'I'he slidable extension member 92 comprises a plate portion 49 formed with side flanges 4l, see Figs. 7 and 8, which are folded upon themselves to provide a double thickness of the metal to reinforce the structure. As shown in Figs. 6 and 7 the* plate portion 49 of the member 52 is cut away centrally throughout the greater part of its` length to form a rectangular opening 42 with a cross strip 43 at its outer end and a relatively wide web 44 at its inner end. As further shown in Figs. 6 and 7 the extension member 92 is mounted for telescopic sliding movement in the cover member 9 with the stop 34 projecting through its central opening 42 and its folded side flanges 4i lying wholly within and in sliding contact with the guideways 3i at the sides of the cover member 9. The strap section 5 is pivotally connected with the cross stripl 43 of the member 32 by means of a connector link i5 similar to that previously described.

A box-like housing 46 is mounted on the web portion 44 of the extension member 32, being centrally positioned to adapt it to lie within the opening between the side anges 25 and above the `plate portion i9 of the intermediate foldable element 8` when the members l, 8 and 9 are folded into overlying relationship. As illustrated in Figs. 8 and 9, the housing 46 is fastened to the extension member 52 by tabs 47 on the edges of i i its/walls which are inserted through cooperating slots 48 in the web portion 44 of the member and bent over into engagement therewith. The recess. 28 in the cover member 9 formed by its offset central portion provides a clearance for the clinched ends of the tabs 4l as shown in Fig. 8. With the construction thus far described the extensionl member and attached housing are adapted for free sliding movement between the plate portions I9 and 25 of the foldable members 8 and 9, respectively, when said members are folded in clasped relationship.

The detent means 35, previously referred to, includes a pawl or latching member 49 formed from a strip of sheet-metal with a widened end bent at right-angles thereto to provide an abutment 50 having its ends projecting laterally from `the sides of the member. At its opposite end the member 49 is curved to form a down-turned toe 52 for engagement with the teeth of the ratchet means formed by the transverse strips between the slots 2i in the plate I9 of the intermediate foldable member 8. The abutment end 50 of the latching member 49 lies withinu the described but of less width and having an abutment end adapted to lie against the forward face of the abutment 59. The opposite end of this second latching member 54 is curved to form a pawl 55 which extends in the opposite direction from the toe 52 of the member 49, and the two latching members 49 and 54 are arranged in nested relationship with the pawl 55 projecting through a centrally positioned recess 57'in the toe 52 of the member 49. The end wall of the housing 46 has. a narrower opening 58 below the opening 53 through which the end of the pawl 55 projects. The toe 52 of the pawl 49, as explained abo-ve, is adapted for cooperation with the ratchet means formed by the apertures 2| in the plate I9 of the intermediate foldable member 8, while the pawl 55 is adapted to engage the stop 54 at the end of the cover member 9 to limit the movement of the extension member 32 outwardly thereof. The latching member or pawl 49j is made of resilient material so that its toe 52 may yield as the extension member 32 is slid from its outward position, shown in Fig. 2, to an adjusted position, shown in Fig. 3.

The resilient means for providing limited selfadjustment of the clasp is carried in the housing 49 and, as herein illustrated,` comprises a flattenedl helical compression spring 59. pression spring 59 acts between the abutment 50 on the latching member 49 and the end wallof the housing 45 to normally hold the abutments 54 `and 55 against the opposite end wall of the housing formed with the openings 53 and 58. The spring Eil is adapted to yield to allow sliding movement of the extension member 32 with respect to the detent means 35 to permit the member to be partly extended or withdrawn from the clasp as shown in Fig. 3. When the extension member 32 is drawn outwardly of the folded clasp members the spring 69 is compressed between the end of the housing 46 and the abutment 59 on the latching'rnember 49. The detent means 35 are thus resiliently mounted on the extension member 32 to yieldingly holdthe latter in adjusted position with respect to the folded clasp members.

Fig. 10 illustrates a modified form of detent member 52 having oppositely directed pawls formed integrally in a single strip of sheet-metal. The member 52 is generally similar to the member 49 previously described as having a rightangular abutment 53 formed'at one end and a curved toe 64 at the other end. The material of the member 52 in this latter construction is slitted and the slitted portion bent upwardly to form a stop pawl 55 corresponding with the pawl 5E in the previously-described construction. It will be understood that the modied form of detent means is arranged within the housing 46 in a manner similar to the latching members 49 and 54 with the abutment 59 normally held against the end wall of the housing by a spring but yielding to allow a relative movement of the extension member 32 with respect to the folded clasp members as explained above.

The various parts of the clasp having now been described in detail the method of operation of the complete device will next be explained. Assuming that the parts of the clasping device are in open or extended relationship as shown in Figs. 5 and 6, the bracelet may be slipped over the hand onto the wrist of the wearer. To clasp the bracelet about the wrist the connector element 8 is folded upon the base member 1, see Fig. 4, and the cover member 9 folded upon both members l and 8 in overlying relationship therewith The comas illustrated in Figs. 3, '7 and 8. It will be observed by reference to Figs. 7 and 8 that the side flanges II on the base member 'I t closely between the opposite inwardly-directed flange-portions 30 of the cover member 9 and the side flanges 29 on the intermediate member 8 are nested within the anges I I on the base member. The cover member 9 is pressed firmly against the base member 'I until the detent protuberances I2 snap across the edges of the flange-portions 39 whereby the parts 'I, 8 and 9 are securely clasped together.

When the parts of the device are folded into overlying relationship and clasped together with the member 32 extended from the cover member 9 the bracelet will encircle the wrist more or less loosely-and to adjust it to a snug iit the clasp is manipulated in the manner as next explained. To reduce the length of the bracelet the member 32 is slid longitudinally of the clasp from the position shown in Fig. 2 to that shown in Fig. 3, during which movement the pawl 52 rides over and engages successively with the edges of the cross strips separating the apertures 2| on the plate I9. When the member 32 has been slid inwardly to the position required to effect a snug t of the bracelet about the wristfpressure on the member 32 is relieved and the pawl comes to rest with its end engaging the edge of one of the apertures ZI. As the apertures 2l are relatively small and closely spaced a close adjustment of the member 32 on the clasp may be made to draw the ends of the bracelet together.

However, to secure a ner adjustment to insure a comfortable fit of the bracelet and to permit it to yield with the flexing of the wrist the extension member 32 is movable with respect to the detent means 35 under the yielding action of the spring 6I) extending between the end of the housing 45 and the abutment 5I). As the extension member 32 is extended from the cover member 9 after the detent means has been adjusted in position the spring 65 will be compressed between the abutment 59 and the end of the housing G6 as shown in Fig. 3. In this manner the bracelet ls caused to be held snugly about the wrist of the wearer while being allowed to expand and contract with the flexing of the wrist.

When it is desired to remove the bracelet from the wrist the device is unclasped by inserting the finger nail under the lip of the finger-grip 33 and prying the cover member 9 upwardly whereby to free the detent protuberances I2 on the side flanges of the base member 'I from the inwardlydirected flanges 39 on the cover member 9. The members 1, 8 and 9 may then be swung about their respective hinge pins I'I and 25 and opened out in the manner as illustrated in Figs. 5 and 6. As the intermediate foldable member 8 is moved away from the cover member 9 the ratchet means formed by the slots 2l in the plate I9 are moved out of engagement with the toe 52 of the pawl 59. This release of the pawl allows the extension member 32 to slide outwardly from the cover member 9 to a position where the pawl 55 engages the stop 34 to prevent disconnection of the parts of the clasp.

It is to be observed from the foregoing that the present novel form of clasping device provides for manually adjusting the length of the bracelet each time it is applied to the wrist while permitting a limited expansion and contraction thereof to secure a comfortable t and compensate for exing movement of the wrist. It will further be observed that the invention provides for a resilient connection between the extension member and detent means which is of simple construction lending to economical manufacture and assembly.

As another feature of improvement, the adjusting means is completely enclosed within the clasp and the device provides a structure which is extremely neat and ornamental in appearance and at the same time efficient in operation and durable over long periods of use.

While I have herein shown and described a preferred form of construction of the device, by way of example, it is to be understood that various modifications may be made in the form and arrangement oi the parts thereof without departing from the spirit or scope of the invention. Therefore, without limiting myself in this respect, I claim:

1. A clasping device of the type indicated comprising a plurality of foldable members, a slide slidably mounted on one of said members to adapt it to be extended longitudinally thereof, cooperating detent means for maintaining the slide in adjusted position, said detent means having its parts so constructed as to slide past each other in the manner of a ratchet to adapt the slide to be slid into the clasp while resisting its extension therefrom, and resilient means connecting the slide with a part of the detent means and yieldable to adapt the slide to be extended from the clasp.

2. A clasping device comprising a plurality of foldable members, an extension member slidably mounted on one of the foldable members to adapt it to be longitudinally extended with respect thereto, cooperating pawl-and-ratchet means for maintaining the extension member in adjusted position with respect to the member on which it is mounted and yieldable to adapt the extension member to be contracted in relation to said foldable member, and a spring connecting an element of the pawl-and-ratchet means with one of the members and yieldable to permit the extension member to be extended from the clasp.

3. A clasping device of the type indicated comprising a plurality of foldable members, an extension member slidably mounted on one of said foldable members, ratchet means on another of the foldable members, detent means on the extension member for engagement with the ratchet means, and resilient means acting between the extension member and detent means for yieldingly holding the extension member in adjusted position with respect to the foldable members.

4. A clasping device of the type indicated comprising a plurality of foldable members, an extension member slidably mounted on one of said foldable members, ratchet means on a cooperating foldable member, an abutment on the extension member, detent means on the extension member for engaging the ratchet means, and resilient means for normally holding the detent means in engagement with the abutment whereby the extension member is yieldingly held in adjusted position with respect to the foldable members.

5. A clasping device of the type indicated comprising a plurality of foldable members, an extension member slidably mounted on one of said foldable members, ratchet means on a cooperating foldable member, detent means on the extension member for engaging the ratchet means, said ratchet and detent means permitting sliding movement of the extension member into contracted relation with the foldable members, and a spring acting between the extension member amazes and detent means for yieldably holding the eX- tension member in adjusted position with respect to the foldable members.

6. A clasping device of the type indicated comprising a plurality of members foldable into overlying relationship., an extension member slidably mounted with respect to the folded members, interengaging means including a pawl on the extensionmember and a ratchet on one of the foldable members, said pawl and ratchet permitting the extension member to be slid into contracted relation with the folded members to adjust the length oi the device, an abutment at theend of one of the foldable members, and resilient means acting between the extension member and pawl to yieldingly allow a limited movement therebetween, said pawl being adapted to engage the abutment to limit the outward movement of the extension member.

7. A clasping device of the type indicated comprising a plurality of members foldable into overlying relationship, an abutment at the end of one of said members, an extension member slidably mounted on one of the members, an` abutment on the extension member, a pawl slidable on the extension member and having means engaging the abutment on the extension member, a ratchet on one of the foldable members cooperating with the pawl to hold the latter in adjusted position, and resilient means acting to normally engage the pawl with the abutment on the extension member to yieldngly hold the latter in adjusted position with respect to the member on which it is mounted, said pawl being adapted to engage the abutment on the foldable member to limit themovement of the extension member outwardly thereof.

8. A clasping device of the type indicated comprising a plurality of members foldable into overlying relationship. including a cover member having side and end flanges, an extension member slidable on the cover member between the side anges, a housing on the extension member having an opening in its end, a latching member having an abutment located within the housing for engaging the end wall thereof and a pawl extending outwardly through the opening in the housing, said pawl having a forked end, a ratchet on one of the foldable members, and a spring within the housing for normally holding the abutment on the latching member in engagement with the end wall of the housing but yielding to permit relative movement of the extension member with respect to the latching member, one of the ends of said pawl engaging the ratchet to hold the extension member in adjusted position on the cover member and the other end being adapted to engage the end ange of the cover member to limit the outward movement of the extension member with respect to the housing.

9. A clasping device of the type indicated comprising a plurality of foldable members, an eX- tension member slidable between the members when the latter are folded into overlying relationship, ratchet means on one of the foldable members, a housing on the extension member having an opening in one side thereof, a latching member positioned within the housing and having an abutment for engaging the end wall thereof and a pawl extending outwardly through the opening for engaging the ratchet means, said ratchet means allowing the pawl and extension member to be moved inwardly between the folded members, and a spring within the housing for normally holding the abutment on the latching member against the end wall of the housing to yieldingly hold the extension member in adjusted position with respect to the folded members.

l0. A clasping device of the type indicated comprising a cover member having side and end iianges, a foldable member adapted to cooperate with the flanged sides of the cover member to form an enclosure, ratchet teeth on the cooperating foldable member, an extension member slidably mounted between the members, a housing fixed to the extension member and having an opening in one side thereof, a latching member extending through the opening in the housing and having an abutment for cooperation with the end wall of the housing, oppositely-directed pawls at the end of the latching member, and a spring within the housing for normally holding the abutment on the latehing member in engagement with the end wall of the housing while yielding to allow the housing to move with respect to the latching member, one of said pawls being adapted to engage the ratchet teeth to yieldingly hold the extension member in adjusted position with respect to the foldable members and the other of said pawls being adapted to engage the ange at the end of the cover member to limit the outward movement of the extension member.

CHARLES H'. KESTENMAN. 

